Windshield wiper having a curved spring wiper arm



Oct. 14, 1952 H. N. WYLlE 2,613,385

WINDSHIELD WIPER HAVING A CURVED SPRING WIPER ARM Filed July 9, 1947 Patented Oct. 14, 1952 WINDSHIELD WIPER HAVING A GURVED SPRING WIPEE ARM Hamilton; Neil Wylie, Richmond, Engl nd. as.

signontoDunlup Rim & WheeLCo. Ltd. London, England,a British corporation.

Application-J-ulyfl, 1947, Serial No: 759,815 In Great Britain July 5, 1945* Section 11, Bublic Law 690,-.Al1g .946f Patent. expires July 5,1965

G GIaims. 11"

My invention relates, to windshield wipers of the. type whichcomprise a pivoted or otherwise movable curved'spring arm carrying a rubber or other squeegee whichactually contacts the surface to be wiped;

Such windshield wipers. are, commonly employed in connection with flat Windshields and the chief object of the present invention is to provide an improved screen wiper which-will be capable ofwiping; screens havinga curved surface, particularly curved, screens such as are commonly used on aircraft,

A, further Object of the invention is. to connest the arm carrying the squeegee directly to the operatingshaft and thus dispense with the intermediate radius member which. is usually connected tothe centre of themember carrying-v the squeegee. v

A still further-object of-the invention is to provide anarm and squeegee which can be saturatedwith defining fluid.

A.\vindshield..wiper. ofthe typeset forthandin accordance with the present invention is provided with a wiping assembly which comprises an arm carrying a squeegee of relatively soft material, the assembly being flexible and initially curved throughout its length and of a stiffness which increases from the tip to the root.

It is preferred that the arm shall comprise a series of superimposed laminations of springy steel or similar material which are of progressively increasing length, the arm being of progressively increasing thickness and stiffness from its free end to its point of attachment with the central shaft which is operated by the actuatin motor, the squeegee being in the form of a rubber or rubber and fabric member bonded or otherwise secured to the arm throughout its length.

The fabric may be incorporated simply to reinforce the casing and/or blade of the squeegee or may comprise an outer covering of absorbent material capable of soaking up de-icing fluid supplied to it preferably near the base of the assembly by a wick or tube, or by a spray.

In order that the invention may be clearly understood and readily carried into effect the invention is hereinafter described with reference to the accompanying drawings, in which:

Figure 1 is a side elevation of a windshield wiper arm in accordance with the present invention the component being shown in a flat straight condition;

Figure 2 is a plan of the same;

Figure 3 is a side elevation of such an arm Figure 4, is a. transverse section onthe line--A--B- in Figure 3 but showing; a fabric envelope;

Figure 5- is aside elevation on a reduced scale showing the initial curved form of the arm and squeegee andvshowing a liquidsupply tube;

Figures 6" and 7' are respectively'side and end elevations illustrating a modification.

Referring now to the accompanying drawings which illustrate a, preferred embodiment of the invention, the windshield wiper arm is built up froma series oflaminationsl of spr-ingy steel or other suitable resilient material; the laminationsnearer the windshield' beingprogressively longer from the supported end to the free end as is clearly shown in Figuresl and 2. The laminations-at the-thick end of the arm are-mounted in a: broached hole in a pivoted base 2" and' are securedby-awedgefl andlocked in position therein by means of, a rivet or-other suitable securingmember- 3-, the base being bored asat 4'- for mounting-in position on a shaft towhich it is clamped by a bolt in hole 9. The shaft is capable of angular movement to move the arm over the surface of the windshield which is to be wiped.

The arm is of the initial curved formation shown in Figure 5, being of arcuate shape throughout its length. The advantage of such an arrangement is that each lamination being shorter than the next the bending resistance of the laminated arm increases at a predetermined rate from the free end to a maximum value at the base. It is preferred that the various laminations shall be of the tapered formation clearly shown in Figure 2. The curved formation of the arm enables the squeegee to maintain a substantially uniform pressure throughout its length on the windshield irrespective of the latters degree of curvature.

The squeegee is preferably in the form of a rubber moulding and comprises a casing 5 of rectangular formation having an integral projecting squeegee portion 6 adapted to make edge contact with the surface of the windshield to be wiped, the casing 5 surrounding the arm and being, if necessary, bonded or otherwise secured in position thereon.

In Figure 4 an envelope of absorbent fabric is shown surrounding the arm and part of the blade and in Figure 5 a rubber tube In is indicated. This tube may convey a metered supply of de- 1c1ng fluid to the absorbent envelope in known manner.

If desired, the free extremity of the arm may be fitted with a wheel or roller 1, such as is indicated in Figures 6 and 7, for the purpose of relieving the pressure exerted by the tip of the arm on the surface of the windshield.

Although in the construction illustrated the arm is intended to have an angular movement relative to the windshield, this movement may be a reciprocating one and it will be appreciated that the inherent resiliency of the arm will permit the arm to change its shape throughout its length to suit the curvature of any part of the windshield with which the squeegee is actually in contact, the windshield wiper therefore being capable of wiping Windshields which are flat or of curved formation in one or two planes.

It is preferred that the arm and squeegee shall have an initial curvature of quite small radius in comparison with the radius of curvature of the windshield to which it is fitted so as to ensure of an adequate pressure being exerted on the windshield even though the radius of curvature of the windshield may differ in different directions, the arm being so designed that it has sufiicient inherent resiliency to maintain an adequate wiping contact between the squeegee and the windshield irrespective of the windshields radius of curvature.

Having described my invention, what I claim is:

1. A windshield wiper which comprises a pivoted base, a spring wiper arm mounted on said base, curved in a plane radial to the pivotal axis of said base and of progressively decreasing stifiness at increasing distance from said base, and a squeegee of relatively soft material mounted directly on said arm lengthwise thereof and on the inner side of its curvature.

2. A windshield wiper which comprises a pivoted base, a spring wiper arm mounted on said base, curved in a plane radial to the pivotal axis of said base and of progressively decreasing stiffness at increasing distance from said base, and a squeegee of relatively soft material mounted directly on said arm lengthwise thereof and on the inner side of its curvature, said arm comprising a number of superposed laminations of spring material extending from said base, the laminations being of decreasing length from the inner side of said arm to the outer side thereof.

3. A windshield wiper according to claim 1, wherein the wiping assembly comprises a casing of relatively soft material surrounding the arm and having an integral squeegee portion projecting therefrom on the concave side of the arm.

4. A windshield wiper according to claim 2, wherein the wiping assembly comprises a casing of relatively soft material surrounding the arm and having an integral squeegee portion projecting therefrom on the concave side of the arm.

5. A windshield wiper according to claim 1 wherein the free end of the arm carries a wheel adapted to rotate in contact with the surface of the windshield during movement of the wiper arm between its extreme angular positions.

6. A windshield wiper as claimed in claim 1 in which absorbent material adapted to be saturated with de-icing fluid extends along the squeegee.

HAMILTON NEIL WYLIE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,246,829 McWhirter Nov. 13, 1917 1,326,145 Stadeker Dec. 23, 1919 1,498,155 Dorr June 17, 1924 1,675,816 Mokma July 3, 1928 1,684,907 Blake Sept. 18, 1928 2,291,435 Anderson July 28, 1942 FOREIGN PATENTS Number Country Date 427,383 Great Britain Apr. 23, 1935 820,156 France July 26, 1937 

